The present invention relates to the computer system technology for allocating functions to a plurality of computers.
A server system called a blade system is known as a prior art of the server system that is formed of a plurality of servers enclosed within a single chassis. The blade system has a plurality of servers (hereinafter, referred to as blade or blade server) enclosed within a single chassis. Each server is built on one or a plurality of boards (CPU blades). The plurality of blade servers enclosed within one chassis includes servers having a plurality of different functions.
As to the maintenance or the like for the blade system constructed as above, it is popularly practiced that a schedule of operations is previously settled and that the information defined in the schedule is used to deploy and boot the images of the functions of the servers that constitute the blade system, thereby performing the functions on the servers. This maintenance is manually performed. The detailed technical content about the deployment is described in the patent specification of US Patent No. 2005/0010918.
So far, the prior art is not known that automatically changes the architecture, or deployment of the blade servers in the blade system of this kind.
The conventional blade system has a plurality of blade servers of different functions mounted to mix, but generally the functions of these blade servers cannot be recognized at a glance from the appearance. Therefore, during the maintenance, the operator might check out wrong blade servers by mistake. In addition, the conventional blade system (computer system) has another problem that, when any one of the onboard blade servers stops its operation due to a failure, the loads on the servers of each function are unbalanced, and thus the load on a blade server might be too large to offer enough service so that the blade system might lose the business opportunity.
The architecture of a plurality of CPU blades (computers, blades) to which one service is to be allocated in a blade server includes cluster type and SMP (Symmetric MultiProcessor) type. In the cluster type, since the CPU blades are loosely coupled, a service may be allocated over a plurality of blade servers (computer units) if the servers are connected to a network. The expansion of service can be made even within a blade server or even between the blade servers. This expansion of computer system is called “scale out”. On the contrary, in the SMP type, since the CPU blades are closely coupled, the CPU blades are coupled through fast buses and thus the distances between the connected blades are desired to be short (to reduce the communicating time and realize fast communication). Therefore, a service is desired to allocate within the same blade server and to allocate to the adjacent slots. In other words, the SMP type has the restriction that the expansion should be made by allocating to a plurality of CPU blades arranged in sequence within the same blade server. Such blade server expansion is called “scale up”. In the blade system having the scale-out and scale-up types mixed, there is a problem that the CPU blades to be secured for the scale-up implementation within the same blade server might be allocated to the scale-out to thus reduce the freedom of the scale-up implementation. The technical contents of the scale-up and scale-out schemes are described in the patent specifications of US Patent Application Publication Nos. 2005/0053057 and 2004/0267920.